Self-sealing rotor for fluid transferring devices



y 7, 1.953 I. H. LEHMAN 2,644,402

SELF-SEALING ROTOR FOR FLUID TRANSFERRING DEVICES v Filed 001;. 6, 1949 4 l-kq/enzors 15 1/ in JY. Ze/z man A further important feature I Patented July 7, 1953 UNITEDILSTATES PATENT OFFICE 1 SELF-SEALING ROTOR FOR. FLUID TRANSFERRING' DEVICES- Y lirvin HQLelimamKci tlandJndQ 7 Application October 6, 1949, Serial No. 119,831

This invention relates to improvements in rotors of the type-constructed of resilient mate?- rial and having radially extending ,vanes or blades, and'refersparticularly to a rotor which soft rubber or other rubber-like material, which is 'so constructed that it per se functions. as a sealfor the shaft openings in the housing in which the rotor operates.

' Another: important feature of the invention resides in the construction of the rotor vanes or,

blades which results in the sealing of one of the rotor compartments or sectors from the next ad ja'cent rotor compartment or sector, during.ro-- tation of therotor.

of the invention resides in a rotor construction which in accomplishing the sealing functions hereinbefore described, does so with the addition of a-minimum of friction at the sealed surfaces.

"In the drawing, Fig. 1 isa sectionalelevational view of a device employing my improved ro tor; the face of the device being removed.

Fig. 2 isatransversesectionalview taken on line 2*2 "of Fig. 1. w i

Fig. 3 is a perspective View of the rotor em 'ployed in the deviceas illustrated in Figs. 1 a'nd2. Although my improvedrotor may be employed in numerousapplic'ations such as in fluid pumps,

fluid motors, fluid measuring or proportioning devices and the like, for purposes of description my invention' will be described. .in conjunction with its use in a fluid measuring or 'proportioning device for which use it is particularly suitable. 7

1 Referring indetail to 'the drawing" I indicates a -cup shaped housing having an interior compjartment 2. The housing I is provided with a faceplate 3 which may be secured to a circular flange 4 which circumscribes the mouth offthe cup shaped member I, by means of screws 5. The housing I is provided with an intake openmeasuring'or proportioning deviceis usually 'pr'ovided" with a rotating element whereby pre'deter- 5 Claims. (01; "(103 -83)v mentis usuallytimed with another operation which requires the feeding of predetermined volumes of liquid from'the proportioning device to accomplish a given purpose, such: as,,the continuous preparation of a predetermined proportioned mixture. I

In the present construction. the proportioning device may-be interposed in a suitable pipe line, the pipes (not shown) being connected. in the openings 6 and I. A rotor 9, comprising the features of my invention, is positioned within the compartment 2 and comprises a metal core I6 having a cylindrical external surface upon which is mounted a substantially cylindrical sleeve II constructed of resilient material such like material. The sleeve II is preferably vul- Canized tothe surface of the core I0 or united Projectingradially from the sleeve are a plurality of vanes I2 which are coextensive with the length of the sleeve and are angularly spaced fromeach other.

The rotor9 is mounted upon a shaft I3 journalled in bearings I4 and I5 carried by the face plate 3 and cup shaped member I respectively' In order to render the rotorimmovable upon thei shaft'with respect to rotational movement, the shaft I3 is provided with a flattened portion 'I6 and the core I0 isprovided with an opening H which registers with the flattened shaft.

As animportantfeature of myinvention: the end surfaces of the core I0 and sleeve II are dished inwardly as shownbest at I8 in Fig.2, that is, the endsurfaces of the core and sleeve comprise essentially inwardly extending conical surfaces. the housing and seating of the face plate 3 tends to compress the outer edges II of the opposite ends of the sleeve I I. In other words, the length of the cylindrical sleeve II, along its outer surface is. slightly; greater than the distance between the oppositeinterior walls of thehousing.

ing .16, and 'a'discharge opening], said housing'50 being conveniently mounted upon @a suitable mined volumes of liquid passing throughthe pipe I line may be discharged from the device per revolution'o-f the rotatingelement. In utilizing such devices the rotation of the proportioning elewallsof the housing- It will be noted that this compression is initiated along the circular line of the'edgesII' and the final compression involvesv only annular areas adjacent the lines II. In thuscompressing the annular areas ofv the .ends of sleeve II- adjacent lines II' a seal is provided at the surfacejcontact of said annular areas and the interior side In addition the opposite radial edges I 9 of each of the vanesIZ are'taperedangularly as are alsothelongitudinal peripheral edges 26 of each ofthe vanes; These angularfltapers comprise 'essentially dihedral angles whereby the-defining edgesofeach of the vanes I2 comprise the crest orridge of the dihedral angle.

When the rotor 9 is positioned within the housing theopposite edges. IQ of the vanes I2 are slightly compressed. Likewise, the efiectiverad-ial When the rotor 9 is positionedwithin housing and the edges I9 and 20 of the respective vanes. In a mannerdescribed hereinbefore with respect to sleeve H, the compression of the,

vanes 12 is initiated along the lines;.i9 anew:

where the effective thickness of the vanes is re ducecl. In this manner a seal is provided along the respective areas of contact betweenthe vanes and housing walls. The sealing action afforded by the compression of the vanes effectively pro-* vents leakage of fluid from one sector or compartment defined by the vanes andthe wallof the housing to the next adjacent compartment. In this manner a predetermined volume of fluid may be delivered from the inlet 6 tothe discharge! without any leakage-from one compartment to the next adjacent compartment during rotation of the rotor. V

In view of the fact that the compression of the resilient material comprising the rotor occurs essentially along a relatively small contact area the. friction of the. rotor in moving within the compartment 2 is reduced to a minimum. It will be noted that theoretically contact between the rotor and the interior walls of the housing will occur along the lines I9, 20 and the circular lines ll comprising the peripheral end edges of the sleeve II- Actually, however, the material comprising the rotor at these respective positions is slightly compressed and a degree of surface contact occurs along these designated lines.

However, in view of the fact that the material adjacent the lines 19, 20 and the peripheral lines of the end surfaces of the sleeve I l is of reduced thickness, the material being tapered to the line of contact, the contacting pressure effecting the seal hereinbefore described will not be sufiiciently great to cause excess friction during rotation of the rotor. Yet, the seal will be effective to prevent leakage from the housing and leakage from one rotorcom'partment to the next rotor compartment.

Of course, if the rotor 9 is to be employed as 'a' fluid pump rotor or a fluid motor rotor the degree of compression'of the various areas of contact of the rotor with the housing walls will be increased. However, for relatively low pressure differentials a comparatively slight degree of compression would be efiective to accomplish the desired seal without causing excess friction.

- I claim as my invention:

1. A rotor constructed of relatively resilient material having a central cylindrical portion and a plurality of radially extending vanes, the surfaces of the opposite ends of said cylindrical portion being conically tapered axially and radially inwardly from substantially the peripheries of said end surfaces and the maximum axial length of. said cylindrical portion occurring at its peedges, the maximum axial length of said-sleeve occurring at the periphery of said sleeve, the maximum axial length of said sleeve and the maximum axial length of'said'vanesbeing greater than the distance between opposite interior walls of said housing whereby the outer peripheral edge of the conically tapered end of said sleeve and the tapered edges of said vanes contact the oppo- ,,site1interio;r walls of said housing under pressure to compress and deform the contacting edges of the rotor to provide fluid seals between said contacting edges ofsaid rotor and said housing walls.

3. A rotor constructed of relatively resilient material having a central cylindrical sleeve, a

plurality of vanes carried by said sleeve and extending radially outwardly with respect to said sleeve, the maximum axial lengthof said vanes being substantially coextensive with the maximum axial length of 'saidsleeve, the surfaces of the ends of said sleeve being substantially conically tapered axially and radially inwardly fromsubstantially-the outer peripheries of said endlsurfaces toward the center of said sleeve, the .maximum axial length of said sleeve occurring atits periphery, and the peripheral portions of said vanes being. tapered to edges of relatively restricted area. 1 4. A rotor constructed of relatively resilient material comprising a central cylindrical sleeve having a longitudinal and transverse ,axis, a plurality of radial vanes extending from the outer cylindrical surface of said sleeve, an end surface of said sleeve being. substantially conically tapered inwardly from. the outer periphery of saidend surface with the apex of the conical taper occurring on said longitudinal axis and inwardly from said end :surface toward said transverse axis.

5. In a fluid transferring device comprising a housing having an inlet and outlet and a rotatable shaft journaled in said housing, a rotor constructed of resilient material carried upon said shaft in said housing, radially. extending vanes carried by said rotor for transferring fluid from said inlet tozsaid outlet when the :rotor. is rotated, said rotor comprising a cylindrical sleeve having a longitudinal axis and ,a transverse axis, an'end surfaceof said rotorbeing substantially conically tapered inwardly toward said longitudinal axis with theapex of said conical surface occurring on said longitudinal axis and being disposed inwardly toward the transverse axis of said sleeve to provide a tapered peripheral circular edge at the tapered end of said sleeve,

the maximum axial length of said sleeve being greater than the distance between opposite interior walls of said housing and occurring at the periphery of said sleeve whereby said tapered edge contacts one of said interior walls of said housing under pressure to' compress and deform-said edge to provide a fluid seal between said contacting edge and; said contacted interior wall. i

- IRVIN I-I. LEHMAN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,052,474 Johnson Aug. 25, 1936 2,189,356 Briggs Feb. 6, 1940 2,258,371 Wernert Oct. '7, 1941 2,455,194 Rumsey Nov. 30, 1948 7 2,460,952 Simer Feb. 8, 1949 2,466,440 Kiekhaefer Apr. 5, 1949 2,499,163 Rand Feb. 28, 1950 

